Tuned vibration absorbers (TVAs) are very useful devices which can cancel the motion at their attachment points at a specific frequency. Unfortunately, TVAs only work at one vibration frequency while the items that they are attached to might vibrate over a range of frequencies. This varying frequency range could be due to a change in the natural frequency of a system, or the operating range of the system could include a range of vibratory frequencies over which isolation is needed. Thus, it is very desirable to have a TVA that will automatically tune itself to the frequency of vibration of the system to which it is attached. In recent years, many types of adaptive TVAs have been proposed and implemented in engineering applications. Adaptive TVAs (non-passive TVAs) can be divided into categories. There are semi-active TVAs, active TVAs (ATVAs) and self-tuning vibration absorbers (STVAs). Semi-active TVAs require power external to the vibration in order to adjust the inertial or compliant characteristics of the TVA through some mechanism. ATVAs also require power external to the vibration, but use this power to directly apply a force on the TVA system. Most ATVAs apply a force directly to the TVA mass. Both semi-active and active TVAs require control logic in order to tune the TVA. The complexity of this logic has included methods from classical controls to fuzzy logic and neural networks. The third type of Adaptive TVAs, STVAs, rely completely on the vibration itself for tuning. No external power is required for these devices, and often, no control logic is needed either. The STVA finds the frequency of the input vibration and tunes itself to it.
There is a need for a system and method of accurately and economically absorbing vehicle body vibrations with a varying frequency. There is a need for an economically feasible method of absorbing vibrations with a varying frequency. There is a need for a robust system and method of making mechanical self-tuning vibration absorbers. There is a need for an economic mechanical self-tuning vibration absorber device and method for absorbing vibrations in a varying frequency range.